That I might know the proof of you (ina gnw thn dokimhn umwn). Ingressive second aorist active subjunctive, come to know. Dokimh is proof by testing. Late word from dokimo and is in Dioscorides, medical writer in reign of Hadrian. Earliest use in Paul and only in him in N.T. ( 2 Corinthians 2:9 ; 2 Corinthians 8:2 ; 2 Corinthians 9:13 ; 2 Corinthians 13:3 ; Romans 5:4 ; Philippians 2:22 ). Obedient (uphkooi). Old word from upakouw, to give ear. In N.T. only in Paul ( 2 Corinthians 2:9 ; Philippians 2:8 ; Acts 7:39 ).